[nsp] regexp question

[Jeff]

At 06:05 AM 4/6/2004, Peter L wrote:
>Hi
>I have a question regarding a regular expression I'm trying to fix and
>hopefully someone that's excellent at regular expressions can help me. I
>would like to accept everything from a peer + everyting from the ASs his
>peering with directly. Example:
>Accept:
>1234 1234
>1234 567
>1234 1234 655
>1234 654 654
>Deny:
>1234 654 989
>or
>1234 567 567 2323
>ando so forth..
>So far I have:
>^(1234_)+([0-9]+)*$
>This accepts everthing except when the second AS is prepended(1234 654 654).
>Is i possible to fix this in one expression? Otherwise I have to setup
>filters for every AS and that would not be very dynamic.

Hi Peter,

here is what I currently have in my router:

ip as-path access-list 1 permit ^577_[0-9]*$

This will accept from 577 and anyone directly connected to them.  Now I am 
not sure how to do the double peering (ie: 577 577 _[0-9]*$) in one line.

Jeff.